Suicide Attempts and Completions in Patients With Bipolar Disorder

According to the CDC, in 2004, suicide was the 11th leading cause of death across all age groups and the 10th leading cause of death for persons aged 14 to 64 years; 32,439 people in the United States took their own lives.1 Women attempt suicide about 3 times more often than men, although men are 4 times as likely to complete suicide.2 Anderson and Smith3 reported that suicide was the eighth leading cause of death among men in 2001. Of the 24,672 completed suicides among men, 60% involved the use of a firearm (the use of a firearm was the means of suicide in 55% of all cases).3

Both "static" and "dynamic" factors have an impact on the rates of suicide. Static factors are associated with increased and decreased risks for self-harm. They are not causal but merely increase or decrease the probability of self-harm. Listed in the approximate rank order of risk, the static predictors of risk for a suicide attempt and completed suicide for persons with psychiatric illnesses, as well as some of the more important static protectors, are presented in the Table. Dynamic factors have to do with clinical states, which are subject to dramatic change within narrow time frames—hence, "dynamic."

TABLE

Static factors associated with suicide1

Risks
History of a suicide attempt(s)
History of a psychiatric disorder, particularly a mood disorder
History of alcohol and/or drug abuse
Family history of suicide or exposure to the suicide of another person, especially a person
to whom one is emotionally attached
Family history of childhood verbal, physical, or sexual abuse
Feelings of hopelessness
Barriers to accessing mental health services (including poverty)
Loss of a significant relationship (including bereavement), one's job, financial status, “face” (ie, humiliation)
Easy access to lethal methods
Severe to extreme stressors
Unwillingness to seek help because of stigma of psychiatric illness
Social isolation or interpersonal impoverishment

Protectors
Effective treatment for psychiatric disorders, including substance use disorders
Easy access to a variety of clinical interventions and the availability of support for those
with help-seeking propensities
The existence of an empathic, high-quality doctor/patient relationship
Support of nuclear and extended family
Strong support outside of one’s home (eg, deep-seated friendships and support provided
through relationships within the structure of one's religious community)
Possession of the skills to solve personal problems, resolve interpersonal conflicts, and
handle disputes nonviolently
Cultural values that discourage suicide
Internalized (not merely professed) religious beliefs that affirm the dignity of human life,
promote life-preserving values, attitudes, and confer meaning on human existence

In clinical samples, about 50% of persons with bipolar disorder (BD) were found to have a history of a suicide attempt.4 In the largest epidemiological study on the topic to date, the suicide attempt rate in persons with BD was twice that of individuals with unipolar depression.5

Estimates of the fraction of unipolar patients who commit suicide are subject to considerable variance. Sources of variance include, for example, whether one focuses on outpatients or inpatients, the type of patient studied (eg, those with psychotic versus nonpsychotic depression), and the purity of the composition of the sample. It is not at all unlikely that the results of many studies have been contaminated by the inclusion of subjects with unrecognized bipolar illness.

Miles6 reviewed studies of the prevalence of suicide in patients with various psychiatric disorders and estimated that 15% of those with "primary endogenous" depression committed suicide. Interestingly, the results of this study also indicated that 15% of those with so-called neurotic depression also commit- ted suicide. Avery and Winokur7 also estimated that 15% of those with unipolar disorder committed suicide.

In 1990, Goodwin and Jamison8 presented the results of an exhaustive review of the literature on the relationship between manic-depressive illness and suicide. The findings of the review, which included 30 reports published between 1936 and 1988, showed that 19% of the deaths of 9389 persons with BD were caused by suicide.

The reasons for the seemingly higher rate of suicide in persons with BD compared with those who are unipolar are not known. However, new data provide hints. Simon and colleagues9 studied the relationship between current and lifetime comorbid anxiety disorders and suicidal behaviors. Lifetime anxiety disorders were associated with more than a doubling of the risk of a suicide attempt. Recent research indicates that persons with BD have a much higher comorbid anxiety disorder burden than persons who are unipolar.10-12

This substantially contributes to the higher rate of attempted and completed suicide among persons with BD compared with those who are unipolar. Individuals with BD are many times more likely to suffer from panic disorder, obsessive-compulsive disorder, social phobia, and posttraumatic stress disorder (PTSD) than individuals with major depressive disorder (MDD).10-12

There is a highly significant dose-response relationship between loading for comorbid anxiety disorders and the probability of having had a suicide attempt; the more anxiety disorders one has, the greater the risk for attempted suicide.10,11